Fall is here and winter is quickly approaching, signaling the perfect time to build and install your own bee condo! We receive many emails and inquiries about bee homes, so we thought we should answer your most common questions here.
Who uses bee condos?
* Cavity nesting bees like mason bees (
Osmia spp.) and leaf-cutter bees (
Megachile spp.). These bees typically look for naturally occurring holes in wood (beetle holes) or stems in which to build their nests.
When will bees occupy them?
* Mason bees will be the first to emerge in early spring (Feb-April) and begin using your constructed bee home. Leaf-cutter bees begin emerging from their nests in late spring into summer (April - July). Adult females will begin provisioning them with nectar and pollen shortly after they emerge from their nests and mate.
How do I know if bees are using them?
* Watch for bees entering and exiting the holes with bellies full of pollen, mandibles full of mud, and leave pieces tucked underneath them. When the bee is finished with one nest, she will
plug the entrance hole with either mud or leaf pieces, so keep your eyes on the holes too!
How long will the bees be in the nests developing?
* Most of these bees have just one generation a year, so the nests will stay occupied until the following spring or summer. The adults will long have passed away, but the nest generation will develop over the next year. Look for small holes in the plugs at the end of the nests to know when the new generation has emerged. The new adult bees will chew their way out and you'll notice a small hole in the mud or leaf.
How and when do I clean the holes out?
* This can be tricky, but the holes definitely need to get cleaned out every 2 years or so. Pest populations can build up in the nests if not properly managed, so keep your condo clean in order to keep your guests healthy! You can either line the holes with paper tubes, and replace those each year, or you can re-drill the holes to smooth and clean them out once the new generation has emerged.
Where should I hang the condo when it's finished?
* For the best results, hang the condo somewhere where it gets morning sun and afternoon shade (east facing). This will warm the condo in the morning, which helps the females to get active, then it keeps the condo shaded and cool in the afternoon so the developing brood doesn't cook inside. Also, make sure it has a roof or is under an overhang, so it doesn't get wet from all the "rain" we are scheduled to get this year!
Here are some good sites for instructions on building your own condo. We don't recommend purchasing bees over the internet as you could unknowingly be transferring diseases and pests into your local bee population. If you build it....they will come!